/*
 * Copyright 2008 Web Cohesion
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.security.oauth.provider;

import org.springframework.security.core.AuthenticationException;
import org.springframework.security.oauth.common.signature.UnsupportedSignatureMethodException;
import org.springframework.security.web.AuthenticationEntryPoint;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

public class OAuthProcessingFilterEntryPoint implements AuthenticationEntryPoint {

    private String realmName;

    public void commence(HttpServletRequest request, HttpServletResponse response, AuthenticationException authException) throws IOException, ServletException {
        if (authException instanceof InvalidOAuthParametersException) {
            response.sendError(400, authException.getMessage());
        } else if (authException.getCause() instanceof UnsupportedSignatureMethodException) {
            response.sendError(400, authException.getMessage());
        } else {
            StringBuilder headerValue = new StringBuilder("OAuth");
            if (realmName != null) {
                headerValue.append(" realm=\"").append(realmName).append('"');
            }
            response.addHeader("WWW-Authenticate", headerValue.toString());
            response.sendError(HttpServletResponse.SC_UNAUTHORIZED, authException.getMessage());
        }
    }

    public String getRealmName() {
        return realmName;
    }

    public void setRealmName(String realmName) {
        this.realmName = realmName;
    }

}